<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
  
    <style>
        #app{
            width:200px;
            height: 200px;
            background-color: red;
            position: relative;
        }
    </style>
</head>
<body>
    <div id="app">

    </div>
    
    <script>
        var app = document.getElementById("app");
        setTimeout(()=>{
            app.style.left = "100px"
        },1000)
        
    </script>
</body>
</html>